Bot both creates a PR and complains about no contributions when extra text in comment

[JoshuaKGoldberg]

Describe the bug

With a(n accidentally) specially crafted comment, I've tricked the bot into both creating a PR and saying in the same comment that it couldn't determine any contributions:

@JoshuaKGoldberg

I've put up a pull request to add @JoshuaKGoldberg! 🎉

I couldn't determine any contributions to add, did you specify any contributions? Please make sure to use valid contribution names.

https://github.com/JoshuaKGoldberg/template-typescript-node-package/pull/429#issuecomment-1546457872

To Reproduce

Steps to reproduce the behavior:

1. Set up allcontributors in a new repo
2. Post a comment with content after the @all-contributors please add ... line

Expected behavior

The bot should ignore the extra content

Additional context

I posted some more comments on that PR. It looks like the bug might have something to do with text like all-contributors existing?

[dannogr]

Hello man, great job!